Vegetation control by steam treatment in boreal forests: a comparison with burning and soil scarification

  • Published source details Norberg G., Jäderlund A., Zackrisson O., Nordfjell T., Wardle D., Nilsson M. & Dolling A. (1997) Vegetation control by steam treatment in boreal forests: a comparison with burning and soil scarification. Canadian Journal of Forest Research, 27, 2026-2033.


This study is summarised as evidence for the following.

Action Category

Prepare the ground before tree planting

Action Link
Forest Conservation
  1. Prepare the ground before tree planting

    A replicated, randomized, controlled study in 1991-1996 in boreal forest in Sweden (Norberg et al. 1997) found that site preparation treatments increased the growth rate of planted Scots pine Pinus sylvestris seedlings. Seedling height was higher in scarification (300 mm) than control plots (250 mm), and highest in steamed plots (steamed: 350 mm; burned: 280). Stem basal area (mm2) differed among all treatments (control: 29; burned: 43; scarification: 55; steamed: 73). In August 1992, five plots (0.6 × 0.6 m) of each control (untreated), burned (ground vegetation and litter burned using a propane burner), scarification (humus layer removed from the mineral soil) and steamed (amount of steam equivalent to 13 L of water evenly sprayed over each plot for 2 minutes) treatments were replicated in 40 blocks that were clearcut in 1991–1992. In June 1993, one scots pine seedling was planted in each plot. Data were collected in 1996.


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